Project Summary/Abstract The Population Research Institute (PRI) and Graduate Program in Demography at the Pennsylvania State University request a five-year renewal of our NICHD T32 training program in population studies, with a focus on Social Environments and Population Health. We request support for 5 predoctoral and 2 postdoctoral training slots for each year of our grant. This is an increase from 4 predoctoral and 1 postdoctoral trainees from our last application because we have expanded the number of participating faculty members in this training effort from 29 to 36 and participating academic programs from 3 to 6 due to new faculty hires and new connections across the university. We draw upon the strengths of our innovative, multidisciplinary, dual-degree Ph.D. Graduate Program in Demography; other participating programs, including Sociology, Human Development and Family Studies, Anthropology, Rural Sociology, and Health Policy and Administration; and the Population Research Institute (PRI). This combination makes Penn State a center of excellence for multidisciplinary research and training in population health. The proposed predoctoral program integrates strong training in demography (demographic theory, methods, and fertility, health/mortality, and migration) with population health perspectives and methods from several programs. The postdoctoral program likewise is focused on enhancing research and training in social environments and population health. Predoctoral trainees are recruited from the approximately 263 annual applicants to, and students currently enrolled in, the five participating academic departments that partner with the signature Dual Degree program in Demography. Over the past ten years of our T32 grant, 100 percent of NICHD pre- and postdoctoral trainees have either been awarded their dual-degree Ph.D. in Demography or completed their program, or are currently enrolled and on track to successfully complete their program. Of the 30 previously appointed trainees who graduated, 87 percent are currently working in research or research-related fields, or pursuing further research training. Our trainees have moved into positions in academia, government, and research and policy organizations, where they continue to produce high quality research and publications, and influence national programs and policies that affect the health and well-being of families, communities, and nations.